The present invention generally relates to an apparatus for mammography, more particularly relates to a combination of a bed structure for supporting a patient, a breast holding mechanism for keep the breasts of the patient in position during mammography, and a camera for taking mammograms from the breasts.
Research shows that breast cancer has reached epidemic proportions worldwide. It is the leading cause of death among U.S. women aged 15 to 54. It takes about 9 years before breast cancer cells are visible on a mammogram. Cancerous cells can spread to other parts of the body including the brain. The average five-year survival rate for patients where breast cancer is detected early is 96%. When breast cancer is detected late, the five-year survival rate drops to is 20%. Therefore, early stage detection is critical for improving chances for survival. However, in the early stage when breast cancer is most treatable, it typically produces no symptoms. Due to the limitations of diagnostic technology, the most important physical symptom of breast cancer is still a painless mass. Statistics and data about breast cancer support the fact that early detection is critical.
To date, x-ray mammography is the most effective tool for breast cancer detection, but it suffers from many problems as follows:
It can not tell if abnormalities are cancerous or benign. 10% of patients with breast cancer present with normal mammograms.
Cancer is correctly predicted only 10% to 40% of the time. 60% of biopsies show no cancer and are therefore unnecessary.
It is generally unsuccessful with dense breast tissue (found in 40% of screening aged women).
Breast ultrasound has been used with limited success. Several attempts have been made to apply scintillation cameras to the mammography. However, none of the current methods are expected to be satisfactorily successful for early detection and accurate location of breast cancer or tumour.
Accordingly, there is a need to solve the problems noted above and also a need for an innovative approach to advance the current technologies of mammography.
According to one aspect of the invention, there is provided an apparatus for mammography. An apparatus for mammography (a) a bed structure having a patient platform on which a patient lies face down, the patient platform having at least one opening through which the breasts of the patient hang down when in use, (b) a mechanism for holding the breasts which extend down through the opening in selected substantially fixed relation relative to the platform, the mechanism being adapted to accommodate the breasts without substantially distorting the inherent shapes of the downwardly extending breasts, and (c) a camera for providing a mammographic image of the breasts as they are being held by the mechanism.
The mechanism includes a pair of breast containers for accommodating the breasts while maintaining substantially the shape of the breasts in the field of view of the camera.
The camera is adapted to receive radiant energy from the patient breasts after the patient has been administered with a radiopharmaceutical substance, while substantially reducing the amount of radiation received by the camera from the remainder of the patient""s body.
The breast containers has the shape of an inverted half-cone sectioned vertically through the vertex thereof, preferably the shape of an inverted truncated half-cone sectioned vertically through the vertex thereof. The breast containers can have the shape of a flaring chute. The breast holding mechanism further includes a plurality of pushing pads for further holding the breasts and fitting them into the breast containers. The breast container has a plurality of perforations so that a surgical tool or a biopsy gun is accessible to the breast through the perforations
The breast holding mechanism is slidably and detachably attached to the bed structure. Therefore, the distance between the breast holding mechanism and the bed structure is adjusted depending on the size of the breasts of patients.
The bed structure further comprises means for rotating the patient platform to both sides thereof about an axis normal to the platform passing through a region intermediate the pair of breast containers. The patient platform is rotated about a vertical axis passing through the cleavage area between of both breasts of the patient when lying face down on the patient platform.
The bed structure is provided with an aperture for accommodating the face of the patient. The bed structure is provided with means, under the aperture, for distracting the patient from mammography. The distracting means includes an artistic picture.
The camera comprises a first scintillation camera having a first collimator, the first collimator defining a first camera surface, a second scintillation camera having a second collimnator, the second collimator defining a second camera surface, wherein the first ant second scintillation cameras are fixed relative to each other such that the first and second camera surfaces together form a xe2x80x9cVxe2x80x9d shape. The breast holding mechanism is located within the confines of the xe2x80x9cVxe2x80x9d shape, thereby allowing mammographic images of both breasts of the patient to be provided simultaneously. The camera can also have access to the armpit area of the patient such that the axillary lymph nodes can be viewed by the camera.
The apparatus for mammography further comprises a radiation source for determining the relative position of the breast to the camera. Also, the apparatus further comprises means for shielding radiation from each other breast. The shielding means is located to prevent a cross-talk between the first and second scintillation cameras.
The collimator holes of the collimators are slanted relative to the camera surfaces such that radiation from other body parts of the patient is substantially prevented from being received by the camera. The slant collimator holes are parallel to the transversal direction of the patient platform, and thus substantially parallel to the chest wall of the patient when lying face down an the patient platform. For example, the first and second camera surfaces are at about 90 degrees with each other, and the collimator holes are at about 45 degrees with the camera surfaces.
According to another aspect of the invention, there is provided a patient supporting structure for using in the examination and treatment of women""s breast. The patient supporting structure comprises the bed structure and the breast holding mechanism, which are noted above.
A further understanding of the other features, aspects, and advantages of the present invention will be realized by reference to the following description, appended claims, and accompanying drawings.